Hmmmm, OK...... I know what you mean about the twist adding power, I've always been taught to twist the hand from palm up to palm down for a punch. I guess the corkscrew adds another 90 degrees in there. I'm still not convinced, but I havent had a chance to try it out yet (damn my lack of a punchbag!)

Not to get too pedantic, but I'd use the description "Spinning back kick" to signify a donkey style kick, where, unlike a spinning side kick (which is what I'd call the kick described above), the body isn't fully turned around and the foot is usually vertical when it makes contact with the opponent.